Performance evaluation of an architecturally-designed vertical high capacity linear slot diffuser in a tropical atrium

Abstract

This paper proposed a new approach for the efficient air conditioning of large tropical buildings. The current study has two objectives: the design and numerical investigations of the performance of vertically oriented high capacity linear slot diffusers (HCLSD) in an atrium building and the verification and validation of the different turbulence models through laboratory-scale experiments. The HCLSD was investigated with varying angles of inclination of the blades (ϕ = 0o to 25o) for the in-depth performance analyses. The performance was evaluated by monitoring and comparing the velocity and temperature profiles along the vertical lines drawn at different locations in the studied domain. A relatively longer jet throw was noticed through quantitative analysis at ϕ = 0o. Note that more than 33% increment in the face velocity was recorded at this angle. The corresponding terminal velocity of 0.225 m/s was observed at 8 m distance from the diffuser face. The detailed investigations at 0o deflector angle (case-1) were carried out for velocity, temperature field, and thermal comfort indices, i.e. PMV and PPD models. For the occupied zone, the thermal comfort indices were found within the acceptable ranges (i.e. PMV = + 0.1 to +0.9 and PPD = 4% to 20%). Abbreviations: ACMV: Air conditioning and mechanical ventilation; CFD: Computational fluid dynamics; CMH: Cubic meter per hour; DV: Displacement ventilation; HCLSD: High capacity linear slot diffuser; IAQ: Indoor air quality; MV: Mixing ventilation; PMV: Predicted mean vote; PPD: Predicted percentage dissatisfied; RANS: Reynolds-Averaged Navier – Stokes; RNG: Re-Normalization Group; SST: Shear-Stress Transport: SIMPLE: Semi-implicit method for pressure linked equations; VAV: Variable air volume; VSD: Variable speed drives